[cherry pick] update verison require & fix typo (#4024)

* udpate verison require & fix typo

README_cn.md

@@ -195,7 +195,7 @@ PaddleDetection模块化地实现了多种主流目标检测算法，提供了
 
 - [安装说明](docs/tutorials/INSTALL_cn.md)
 - [数据准备](docs/tutorials/PrepareDataSet.md)
-- [30分钟上手PaddleDetcion](docs/tutorials/GETTING_STARTED_cn.md)
+- [30分钟上手PaddleDetection](docs/tutorials/GETTING_STARTED_cn.md)
 - [FAQ/常见问题汇总](docs/tutorials/FAQ)
 
 

README_en.md

@@ -96,7 +96,7 @@ Based on the high performance core of PaddlePaddle, advantages of training speed
             </ul>
         </ul>
         <ul>
-          <li><b>Face-Detction</b></li>
+          <li><b>Face-Detection</b></li>
             <ul>
              <li>FaceBoxes</li>
              <li>BlazeFace</li>
@@ -261,7 +261,7 @@ The relationship between COCO mAP and FPS on Tesla V100 of representative models
   - [Vehicle detection](configs/vehicle/README.md)
 - Competition Plan
   - [Objects365 2019 Challenge champion model](static/docs/featured_model/champion_model/CACascadeRCNN.md)
-  - [Best single model of Open Images 2019-Object Detction](static/docs/featured_model/champion_model/OIDV5_BASELINE_MODEL.md)
+  - [Best single model of Open Images 2019-Object Detection](static/docs/featured_model/champion_model/OIDV5_BASELINE_MODEL.md)
 
 ## Applications
 

docs/tutorials/INSTALL.md

@@ -22,6 +22,7 @@ Dependency of PaddleDetection and PaddlePaddle:
 
 | PaddleDetection version | PaddlePaddle version  |    tips    |
 | :----------------: | :---------------: | :-------: |
+|    release/2.2       |       >= 2.1.2   |     Dygraph mode is set as default    |
 |    release/2.1       |       >= 2.1.0   |     Dygraph mode is set as default    |
 |    release/2.0       |       >= 2.0.1    |     Dygraph mode is set as default    |
 |    release/2.0-rc    |       >= 2.0.1    |     --    |

docs/tutorials/INSTALL_cn.md

@@ -18,6 +18,7 @@ PaddleDetection 依赖 PaddlePaddle 版本关系：
 
 |  PaddleDetection版本  | PaddlePaddle版本  |    备注    |
 | :------------------: | :---------------: | :-------: |
+|    release/2.2       |       >= 2.1.2    |     默认使用动态图模式    |
 |    release/2.1       |       >= 2.1.0    |     默认使用动态图模式    |
 |    release/2.0       |       >= 2.0.1    |     默认使用动态图模式    |
 |    release/2.0-rc    |       >= 2.0.1    |     --    |